IL1.beta. is produced by macrophages and has a wide variety of biological activities associated with inflammatory pathologies, such as rheumatoid arthritis or arthrosis.
IL1.beta. stimulates those cells present in joints that produce and then express inducible cyclo-oxygenase (COX2), and inducible NO synthase, to provide prostaglandins and NO, which are important mediators of pain and inflammation. IL1.beta. also activates the expression and production of proteases which are involved in degrading the extracellular matrix of chondrocytes and in suppressing the synthesis of the components of the cartilage matrix.
Moreover, IL1.beta. is involved in activating endothelial cells which then express different adhesion factors, and in inducing other pro-inflammatory cytokines, such as TNF or the chemokines (IL6). Finally, IL1.beta. plays a role in the regulation of bone resorption and in lymphocyte differentiation and proliferation.
An IL1.beta. inhibitor can therefore be expected to be active against inflammatory phenomena and to modify favourably the development of pathologies such as rheumatoid arthritis or arthrosis.